package netWork;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;

public class TcpEchoServer {
    private ServerSocket serverSocket=null;

    public TcpEchoServer(int port) throws IOException {
        serverSocket=new ServerSocket(port);

    }
    public void start() throws IOException{
        System.out.println("启动服务器");
        while (true){
           Socket clientSocket= serverSocket.accept();
                 processConnection(clientSocket);
        }
    }
    //.针对一个链接，提供处理逻辑
    private void processConnection(Socket clientSocket){
      //先打印客户端信息
        System.out.printf("[%s:%d] 客户端上线 ",clientSocket.getInetAddress(),clientSocket.getPort());
        try(InputStream inputStream=clientSocket.getInputStream();
            OutputStream outputStream=clientSocket.getOutputStream()){
            //使用Scanner包装一下 inputStream 可以更方便的读取请求数据
            Scanner scanner=new Scanner(inputStream);
            PrintWriter printWriter=new PrintWriter(outputStream);
            while (true){
                //1.读取请求并解析

                if(!scanner.hasNext()){
                    //如果Scanner中无法读取数据，说明客户端关闭了，导致服务器这边读取到末尾
                    break;
                }
                String request=scanner.next();
                //2.根据请求计算响应
            String response=process(request);
                //3.把响应写回客户端
                //outputStream.write(response.getBytes());
                printWriter.println(response);

                //4.打印日志
                System.out.printf("[%s:%d] req=%s;resp=%s\n",clientSocket.getInetAddress(),clientSocket.getPort(),request,response);
            }
        }catch (IOException e){
            e.printStackTrace();
        }
        System.out.printf("[%s:%d] 客户端下线\n ",clientSocket.getInetAddress(),clientSocket.getPort() );
    }
    private String process(String request){

        return request;
    }

    public static void main(String[] args) throws IOException {
        TcpEchoServer server=new TcpEchoServer(9090);
        server.start();
    }
}
